This week’s worst heat wave will hit Southern California in the coming days.

Prediction

Meteorologists say temperatures in the San Fernando Valley could reach between 110 and 115 degrees. Burbank, Woodland Hills, Pasadena, Santa Clarita and Palm Springs could also experience temperatures in the 30s. And downtown Los Angeles is forecast to see temperatures in the mid to high 90s.

Temperatures in the mid to upper 90s are also expected in Long Beach, said Mike Wofford, a meteorologist with the National Weather Service in Oxnard. Inland Orange County is expected to stay in the 90s, and inland San Diego County could reach 102 degrees.

Elsewhere in the Southland, triple-digit heat is expected. Temperatures could reach 106 degrees in Santa Clarita and 118 degrees in Palm Springs on Thursday. And temperatures in the Inland Empire could reach 112 degrees.

Read more: Extreme heat wave hits Southern California. How bad will it be?

Warnings

The weather service has issued an extreme heat warning for most of Los Angeles County from 11 a.m. Wednesday through 8 p.m. Friday, warning residents that temperatures could reach 95 to 110 degrees Fahrenheit.

Night-time temperatures of around 21 and 27 degrees are not expected to bring much relief from the heat.

Timeline

Wednesday: 94 in downtown LA; 80 in Santa Barbara; 110 in Woodland Hills

Thursday: 97 in downtown LA; 82 in Santa Barbara; 113 in Woodland Hills

Friday: 95 in downtown LA; 82 in Santa Barbara; 111 in Woodland Hills

Saturday: 93 in downtown LA; 80 in Santa Barbara; 108 in Woodland Hills

Fire hazard

Officials also warn of increased fire risk during the stifling heat.

There is a silver lining, however: the extreme temperatures are not accompanied by Santa Ana winds, reducing the risk of fast-moving wildfires driven by wind.

Read more: July was the hottest month on record in California as the climate warms to dangerous new extremes

Safety

Los Angeles Mayor Karen Bass announced this week that hundreds of cooling centers will be open across LA through Friday, including “climate stations” on Skid Row where people can access shade, seating and cold drinks.

Residents can find a list of cooling centers and ‘climate stations’ online.

Stay hydrated

Drinking more water than you normally would, and drinking it before you feel thirsty, will help you stay hydrated. When you’re outside and sweating, the standard is to drink two to four cups of water — or about 16 to 32 ounces — every hour.

Dr. Fausto Farfan, chief of emergency medicine at Kaiser Permanente Woodland Hills Medical Center, also recommends adding electrolytes to water or drinking sports drinks. This helps your body replace the salt and minerals you lose through sweat.

One way to know if you are hydrated enough is to look at your urine. If it is dark yellow or brownish, that is a sign that you need to drink more fluids.

“Generally speaking, the rule of thumb is that if you’re staying well hydrated, your urine should be a light yellow color,” Farfan said. And if you’re peeing less than normal, it’s probably time to drink.

According to the U.S. Centers for Disease Control and Prevention, heat-related illnesses can range from sunburn and heat rash to more dangerous conditions such as heat exhaustion and heatstroke.

Read more: How to stay cool and safe during California’s first summer heat wave

Know the symptoms of heat-related illness

Signs of heatstroke, the most serious of all heat-related illnesses, include a body temperature of 103 degrees or higher; a rapid, strong heartbeat; hot, red, dry, or moist skin; headache; dizziness; nausea; confusion; and fainting. If you or someone you know experiences these symptoms, seek immediate medical attention. In the meantime, the CDC recommends moving to a cooler location and lowering your body temperature with cool cloths or a cold bath, but avoid drinking anything.

According to the CDC, signs of heat exhaustion include heavy sweating; cold, pale, and clammy skin; a fast, weak heartbeat; nausea or vomiting; muscle cramps; fatigue or weakness; dizziness; headache; and fainting. If you have these symptoms, move to a cool place; loosen your clothing; put on cool, wet clothing or take a cold shower; and drink water.

Seek immediate medical attention if you vomit, if your symptoms get worse, or if they last more than an hour.

Protect the most vulnerable

Children, pets, the elderly, the homeless, pregnant people and people with chronic conditions are more vulnerable to heat-related illness.

Farfan said they need much the same precautions as everyone else, but it’s important to keep an eye on them, “kind of a buddy system to keep an eye on them in case they don’t realize they’re getting overheated.”

If you notice that they are red, sweating excessively, have difficulty moving, or are showing other symptoms of heat-related illness, give them some water and help them move to a cooler area.

And never leave a child or pet in a car. Temperatures can rise quickly, even with windows slightly open.

Read more: Heat wave in Southern California brings temperatures to 119 degrees

Stay informed

Los Angeles residents can sign up for extreme heat warnings through the city’s website. You can also check the weather forecast for your area on the National Weather Service website and find weather alerts, warnings and advisories for California and beyond on the National Oceanic and Atmospheric Administration website.

Other tips to stay cool

• Eat foods high in water content, such as watermelon and cucumbers, but limit or avoid sugary, alcoholic, and caffeinated drinks.

• Wear loose, light-colored clothing and a hat for protection.

• Keep pets indoors if possible. If you must keep them outside, make sure they have plenty of shade and water.

• Take a cold shower.

• If possible, avoid using your stove, oven, or other appliances that generate heat.

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This story originally appeared in the Los Angeles Times.